1. Field of the Invention
This invention is in the field of decoders for encoded binary signals, and more particularly relates to an improved decoder for Manchester encoded data signals.
2. Description of the Prior Art
Manchester encoded data signals are extensively used in the transmission of digital data. An advantage to this type of encoding is its self-clocking feature, as well as its ability to increase the integrity of the data transmitted by minimizing noise interference, loss of synchronization and undetected transmission errors. There are two general approaches to decoding Manchester encoded data, one such approach uses an integrate-and-dump technique, and the second uses a sequential operation where nonsignificant voltage transitions between Manchester bit cells are masked in generating a strobe, or receive clock signal.
A problem with prior art Manchester decoders is that they do not identify the binary data values represented by the differing voltage levels of each half-bit cell of a Manchester bit cell, which values can be used to increase the integrity of the data transmitted by identifying Manchester bit cells which represent code violations; i.e., Manchester bit cells in which there is no mid-bit voltage transition.